Portable telephone



FIG. 1 is a front perspective view from above and one side of a portable telephone showing my new design;

FIG. 2 is a side view from the other side;

FIG. 3 is a rear view;

FIG. 4 is a top plan view; and,

FIG. 5 is a bottom plan view. 

The ornamental design for a portable telephone, as shown and described. 